A robotic bird created in conjunction with U.S. Army could be developed into an unsuspecting future war agent.

The Robo-Raven's manoeuvres are so realistic that other birds are fooled into thinking it is one of them.

Its ability to hide in plain sight and light weight could prove valuable in military operations, claim Army Research Laboratory researchers.It weighs just 9.7 grams and has a wingspan of 34.3 cm.

Scroll down for video

Robo-Raven weighs 9.7 grams and has a wingspan of 34.3 cm. Its ability to hide in plain sight and light weight could prove valuable in military operations, claim Army Research Laboratory researchers

Using two actuators for the wings required a bigger battery and an on-board micro controller, which initially made Robo-Raven too heavy to fly. Engineers turned to advanced manufacturing processes such as 3D printing and laser cutting to create lightweight polymer structures

'It already attracts attention from birds in the area which tends to hide its presence,' said John Gerdes, a mechanical engineer at Aberdeen Proving Ground.

Seagulls, songbirds and sometimes crows tend to try to fly in a formation near the bird during testing, but birds of prey, like falcons and hawks take a much more aggressive approach.

Share this article

'Generally we don't see them coming,' Gerdes said. 'They will dive and attack by hitting the bird from above with their talons, then they typically fly away.’

Scientists at the University of Maryland made Robo-Raven out of carbon fibre, thermal-resistant plastic, Mylar foil and foam.

It has the unique ability to flap its wings completely independently of each other, enabling the bird to perform extreme aerobatic manoeuvres.

VIDEO: Robo-Raven performs extreme aerobatics

Using two actuators for the wings required a bigger battery and an on-board micro controller, which initially made Robo-Raven too heavy to fly.

To reduce the weight, engineers turned to advanced manufacturing processes such as 3D printing and laser cutting.

The system now weighs just 9.7 grams and has a wing span of 34.3cm. It can carry a payload of almost six grams.

The system is much quieter than the helicopter or propeller and can get much closer to an adversary without revealing its presence.

'We use hollow stiffeners to provide a stiff and light-weight structure, and our wing spars have been arranged in a fan pattern to create the desired airfoil shape during the flapping motions,' said Gerdes.

'At any time, we can transition between these behaviours with total control over the wings.'

ARL's John Gerdes, center, teamed with University of Maryland fellow graduate student researchers Luke Roberts and Ariel Perez-Rosado to develop the Robo-Raven, a robotic bird that glides, soars and flaps like a real bird.

MECHANICAL MARVELS

The ability to mimic the effortless, swooping flight of birds is an age-old fascination...

The
earliest example of avian automaton is thought to be 350 B.C.E. when the
mathematician Archytas of Tarentum is said to have created a wooden
dove capable of flapping its wings and flying up to 200 meters.

More
recently, the RoboSwift, built by researchers at the Delft University of
Technology, was among the first flying machines with a 'morphing' swing
sweep. Its wings reduce in surface area when pulled back to limit drag,
the way the wings of actual fast-flying swifts do.

Its potential has been recognised by the
U.S Army who is funding research into small and micro scale unmanned
aerial systems that could allow Robo-Raven to fly autonomously.

Currently Robo-Raven cannot fly with sensors due to a very restricted payload, but advanced research is expected to improve their understanding of how a soldier could use it.

The team at Maryland University are also working on developing solar cell wings so that the Robo-Raven can land and charge before resuming a mission.

The project builds on work by Dr SK Gupta, a professor in mechanical engineering at Maryland University, who began working on flapping-wing robotic birds nearly a decade ago.

Currently Robo-Raven cannot fly with sensors due to a very restricted payload, but advanced research is expected to improve their understanding of how a soldier could use it

The team at Maryland University are also working on developing solar cell wings so that the Robo-Raven can land and charge before resuming a mission

Gupta first successfully demonstrated
a flapping-wing bird in 2007. This bird used one motor to flap both
wings together in simple motions.

By
2010 the design had evolved over four successive models. The final bird
in the series was able to carry a tiny video camera, could be launched
from a ground robot, and could fly in winds up to 10 mph.

‘Robotic
birds are expected to offer advances in many different applications
such as agriculture, surveillance, and environmental monitoring,’ said
Gupta.

‘Robo-Raven is just
the beginning. Many exciting developments lie ahead. The exotic bird
that you might spot in your next trip to Hawaii might actually be a
robot.’